How do we study the stars?

Well, by analyzing the light that comes from them. We can measure their velocity, how big they are, what type they are, what are they made of. Light or electromagnetic waves are still our best instrument that we use to learn as much as we can about the Universe.

How do we know what a star is made of? Michel van Biezen, from iLectureOnline, will teach us about the emission spectrum. That spectrum shows a fixed number of lines in the spectrum that are a precise signature of a given element. See:\

Also, how can we calculate what emission spectrum an element might have? Watch this to learn how>: